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CASE REPORTLarge oral focal mucinosis: a case report
Mucinose oral focal: descrição de um caso clínico
Karla Rovaris da Silva1; Bárbara Vanessa de Brito Monteiro2; Thayse Silva Aragão Norões3; Gustavo Pina Godoy4; Márcia Cristina da Costa Miguel5
First submission on 05/08/13; last submission on 09/10/13; accepted for publication on 10/10/13; published on 20/02/14
1. Doctoral student of Oral Radiology at Universidade Estadual de Campinas (Unicamp); Master’s degree in Oral Radiology from Unicamp. 2. Doctoral student of Oral Pathology at Universidade Federal do Rio Grande do Norte (UFRN); Master’s degree in Oral Pathology from UFRN. 3. Dentistry graduate of Universidade Estadual da Paraíba (UEPB).
4. Doctorate in Oral Pathology from UFRN; professor of the Post-Graduate Program in Dentistry at UEPB. 5. Doctorate in Oral Pathology from UFRN; professor of the Post-Graduate Program in Oral Pathology at UFRN.
ABSTRACT
The aim of this article is to report the case of a 23-year-old female patient that sought dental service for examination of an asymptomatic slow-growing large lump in the mandibular gingiva causing displacement of the right irst molar. Excisional biopsy, histopathological analysis, Alcian blue/periodic acid-Schiff (PAS) staining and immunohistochemistry analysis for S-100 were performed. The diagnosis established was oral focal mucinosis. After three years, the patient is still under follow-up, without any recurrences. Although cases of oral focal mucinosis of this particular size are rare, this entity should be considered in the differential diagnosis of oral lesions located in the gingiva.
Key words: connective tissue diseases; connective tissue; Alcian blue.
J Bras Patol Med Lab, v. 50, n. 1, p. 54-56, fevereiro 2014
INTRODUCTION
Oral focal mucinosis (OFM) is an asymptomatic, rarely reported, benign lesion of the oral cavity whose etiology is uncertain(7). Tomich(9) irst described OFM as the oral counterpart
of cutaneous focal mucinosis. It has been suggested that its pathogenesis involves ibroblasts over producing hyaluronic acid at the expense of connective tissue elements(2, 9).
OFM commonly occurs during the fourth to ifth decade of life, and females are more frequently affected than males, with a ratio of almost 2:1(5).This lesion appears as an asymptomatic
elevated swelling, with the same color of the surrounding normal mucosa, and the mucosa directly overlying bone appears to be the particularly vulnerable(6). OFM is 1cm or less in diameter(3-5).
Rarely, the lesion may become secondarily ulcerated(8). In this
article, we report the case of an uncommonly large oral focal mucinosis in a female.
CASE REPORT
A 23-year-old female patient sought dental service for examination of an asymptomatic slow-growing lump in the mandibular gingiva causing displacement of the right irst molar. The lesion was sessile, irm, and the overlying mucosa
was non-ulcerated and presented no colour alterations (Figure
A). The diagnostic hypotheses were peripheral giant cell lesion, peripheral ossifying ibroma and traumatic ibroma. Excisional biopsy and histopathological analysis were performed. In the subepithelial area, circumscribed masses of loose myxomatous tissue were observed, surrounded by dense ibrous connective tissue separating them from the epithelial lining (Figure B). Within
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dispersed throughout the connective tissue compatible with
hyaluronic acid (Figure C). Immunohistochemistry analysis for
S-100 protein showed that the lesion was negative for this marker
in the mucinous area (Figure D). The established diagnosis was
oral focal mucinosis. After three years, the patient is still under follow-up, without any recurrences.
FIGURE – A) Clinical aspect of the lesion causing tooth displacement; B) circumscribed mucinosis area covered with stratiied squamous epithelium; C) alcian blue positivity in mucinosis area; D) immunohistochemistry for S100 showing negativity in the myxoid area and positivity in Langerhans cells
DISCUSSION
According to Narayana and Casey(7), OFM is routinely
misdiagnosed. Histopathological diagnosis becomes important because it is dificult to diagnose this lesion clinically, as there are
no clinical distinctive features(6). OFM can manifest as pyogenic
granuloma, peripheral giant cell granuloma, or peripheral ossifying ibroma(7). In this case, the lesion was particularly large
and caused displacement of the irst right molar, what made an accurate clinical diagnosis impossible.
The histological findings of OFM described in the literature are: a well-circumscribed area of myxoid tissue surrounded by fibrotic tissue. The myxomatosis/mucinosis area is a loose connective tissue composed by an accumulation of hyaluronic acid and collagen fibrils that are widely separated and interspersed with stellate-shaped fibroblasts, with or without inflammation, and covered with stratified squamous
epithelium(1, 2, 5, 7). All the histological features were observed
in the present case.
OFM specimens are Alcian blue-positive, showing strong and diffuse positivity, which conirms the abundant mucin dispersed throughout the connective tissue(2, 8). As the differential diagnosis
also includes myxoid neural lesions, S100 staining is important in establishing the diagnosis, with cases of OFM being negative(1). In
our case, negativity for S100 was observed in the mucinous area, what reinforced the diagnosis of OFM.
Similar to this reported case, a case series(7) described female
predilection, and the majority of lesions were located on the mandibular gingiva. In all reported cases, the histologic features, combined with negative immunohistochemical S-100-protein expression, fulill the diagnostic criteria.
Surgical excision is the recommended treatment for OFM, and recurrences are unusual(7). The present patient shows no recurrence Karla Rovaris da Silva; Bárbara Vanessa de Brito Monteiro; Thayse Silva Aragão Norões;
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RESUMO
O objetivo deste artigo é relatar o caso de uma paciente de 23 anos de idade que procurou o serviço odontológico para exame de um grande nódulo de crescimento lento, assintomático, na gengiva mandibular, o que causou deslocamento do primeiro molar direito. Foram realizadas biópsia excisional, análise histopatológica, coloração Alcian blue/periodic acid-Schiff (PAS) e análise imuno-histoquímica para S-100. O diagnóstico de mucinose oral focal foi estabelecido. A paciente ainda está sob acompanhamento, sem recorrência, após três anos. Embora os casos de mucinose oral focal com esse tamanho sejam raros, esta entidade deve ser considerada no diagnóstico diferencial das lesões orais localizadas em gengiva.
Unitermos: doenças do tecido conjuntivo, tecido conjuntivo, azul alciano.
REFERENCES
1. ALDRED, M. J. et al. Oral focal mucinosis: report of 15 cases and review
of the literature. Pathology, v. 35, n. 5, p. 393-6, 2003.
2. GABAY, E.; AKRISH, S.; MACHTEI, E. E.; Oral focal mucinosis associated with cervical external root resorption: a case report. Oral Surg Oral Med Oral Pathol Oral Radiol Endod, v. 110, n. 4, p. e75-8, 2010.
3. IEZZI, G. et al. Oral focal mucinosis of the gingiva: case report. J Periodontol, v. 72, n. 8, p. 1100-2, 2001.
4. LEE, J. G. et al. Oral focal mucinosis in an adolescent: a case report. Aust Dent J, v. 57, n. 1, p. 90-2, 2012.
5. LIMA, A. A. S. et al. Oral focal mucinosis. Quintessence Int, v. 99, n. 7, p. 611-5, 2008.
6. MADHUSUDHAN, A. S. et al. Oral focal mucinosis: report of two cases. Rev Odonto Cienc, v. 25, n. 3, p. 310-3, 2010.
7. NARAYANA, N. CASEY, J. Oral focal mucinosis: review of the literature and seven additional cases. Gen Dent, v. 57, n. 2, p. e11-3, 2009. 8. TALACKO, A. A. et al. Oral focal mucinosis: report of two cases with ulceration. Pathology, v. 36, n. 6, p. 582-3, 2004.
9. TOMICH, C. E. Oral focal mucinosis. A clinicopathologic and histochemical study of eight cases. Oral Surg Oral Med Oral Pathol, v. 38, n. 5, p.714-24, 1974.
MAILING ADDRESS
Márcia Cristina da Costa Miguel
Universidade Federal do Rio Grande do Norte, Departamento de Odontologia, Programa de Pós-Graduação em Patologia Oral; Av. Senador Salgado Filho, 1787, Lagoa Nova; CEP: 59056-000; Natal-RN, Brazil; Tel.: +55 (84) 3215-4138; fax: +55 (84) 3215-4138; E-mail: mccmiguel@hotmail.com. three years after the surgical excision. This case is particularly
interesting because the lesion was atypical in appearance and size. Furthermore, a tooth displacement was clinically observable.
Although cases of oral focal mucinosis of this size are rare, this entity should be considered in the differential diagnosis of soft tissue lesions in the oral cavity, especially when located in the gingiva.
